1. Field of the Invention
The present invention relates to an air duct structure, and especially to an air duct of a radiating fan which can be installed on the wind outlet of an electronic device and can concentrate or guide airflow to the electronic device in the periphery thereof.
2. Description of the Prior Art
In the general computer mainframe, because of the variation of voltage or accumulation of circuits and components, the temperatures of some electronic devices or components are increased to a high value so as to destroy itself or other adjacent components. Generally, electronic devices or components easy generating high temperature are added with radiator. The most frequently used radiator is radiating fan. The components most easily accumulating a high thermal power are power supplies in addition to CPUs (central processing unit). Therefore, in general, the power supplies and CPUs are installed with radiating fan.
For the radiating fans of power supply, in conventional, the air flows to the casing. Thus, only the waste gas from the voltage change is released. However, in recent computer systems, in order to increase the energy efficiency, in the newly design, the air flows into the casing for generating air convection so that other electronic device without radiator has the function of heating dissipating by the radiating fan. However, since in the prior art, the air flows uniformly and inwards, and thus it can not be concentrated to some predetermined and important places, a part of air flows to places without any electronic devices. While some electronic devices necessarily dissipating heat get no air. Therefore, the heat dissipating efficiency is not good.
Accordingly, it is not necessary to have a novel radiating fan in which the orientation and amount of air flow can be adjusted so to increase the heat dissipating efficiency.